Interfacial reactions: mixed order kinetics and segregation effects

نویسندگان

  • O'Shaughnessy
  • Vavylonis
چکیده

We study A-B reaction kinetics at a fixed interface separating A and B bulks. Initially, the number of reactions R(t) approximately tn(infinity)(A)n(infinity)(B) is second order in the far-field densities n(infinity)(A), n(infinity)(B). First order kinetics, governed by diffusion from the dilute bulk, onset at long times: R(t) approximately x(t)n(infinity)(A), where x(t) approximately t(1/z) is the rms molecular displacement. Below a critical dimension, d0) leads to anomalous decay of interfacial densities. Numerical simulations for z = 2 support the theory.

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عنوان ژورنال:
  • Physical review letters

دوره 84 14  شماره 

صفحات  -

تاریخ انتشار 2000